1. Field of the Invention
The present invention generally relates to a method for manufacturing an improved solar cell module, more particularly to a method for manufacturing the improved solar cell module that may not happen problems of power leakage and short circuit.
2. Description of the Prior Art
Among the recent world spread consciousness of ecological and environmental protection issues, the deepest concern is directed to the warming of the earth by CO2 production, and the development and stable supply of clean energy are urgently desired objectives. The solar cell is one of the most promising clean energy sources because of its safety and ease of handling. Solar cells have been prepared in various forms such as (a) monocrystalline silicon solar cells; (b) polycrystalline silicon solar cells; (c) amorphous silicon solar cells; (d) copper-indium selenide solar cells; and (e) compound semiconductor solar cells. Among these types of cells, the thin film crystalline silicon solar cells, compound semiconductor solar cells, and amorphous silicon solar cells are recent targets of active development as they are relatively inexpensive and can be formed into a large area.
Traditional manufacturing processes of solar cell modules have the steps of: (a) making a plurality of solar cell strings; (b) arranging the solar cell strings to be a solar cell matrix; (3) processing lamination process with a piece of glass as front sheet, first ethylene-vinyl acetate (EVA) as isolating cover, the solar cell matrix, second ethylene-vinyl acetate (EVA) as isolating cover, and back sheet in series; (4) wiring the laminated solar cell matrix with a junction box; and (5) assembling the laminated solar cell matrix with the junction box with an aluminum frame to form the traditional solar cell module. However, there are some problems that need to be improved.
Before the module is in the lamination process, the conductive wires are commonly connected with the junction box by passing through the first EVA, second EVA and back sheet. Some shortcomings follow. First, since the conductive wires go through the first EVA, the second EVA and the back sheet, the EVA, the second EVA and the back sheet need to be punched or cut before lamination process. In order to avoid the solar cell strings from shifting during ribbons, end points of the conductive wires, going through the holes, tapes are required to fix them together. However, the tapes may cause stability problem for the solar cell module in long term.
Secondly, power leakage and even short circuit still exist. When the solar module is under the manufacturing processes, non-insulated cables are commonly used to connect the conductive wires and the junction box. If the conductive wires are too close one another, the solar cell module will easily have power leakage or short circuit between the ribbons when generating electric power. Furthermore, it causes danger to human bodies and fire.
With references to FIG. 12A to FIG. 12D, which illustrate schematic sequential views of forming an isolating member between conductive wires to prevent problems of power leakage and short circuit in prior arts. As shown in FIG. 12A, a front sheet 203′ is a bottom layer, a first isolating cover 212a′ is beyond the front sheet 203′, and a plurality of conductive wire sets 2016′ are on the first isolating cover 212a′ and defined as another layer that is the same as a layer where the solar cell matrix is on, wherein each of the conductive wire sets 2016′ may have a pre-process that is to vertically bend the conductive wire sets 2016′, and the pre-process is applicable to electrically connect the conductive wire sets 2016′ with a junction box; as shown in FIG. 12B, an isolating member 80′ is disposed between two conductive wire sets 2016′, each of the conductive wire sets 2016′ has one conductive wire 20161′ and one conductive wire 20162′, wherein the conductive wire 20162′ penetrates through a seam 212a5′ on the first isolating cover 212a′, then it can be seen that the arrangement lets the isolating member 80′ isolates the conductive wire 20161′ and the conductive wire 20162′; as shown in FIG. 12C, a second isolating cover 212b′ is on the layer with the conductive wire sets 2016′, so that the isolating member 80′, the partial conductive wire 20161′ and the partial conductive wire 20162′ are shown by dot lines since they are covered by the second isolating cover 212b′, but other part of the conductive wire 20161′ and other part of the conductive wire 20162′ penetrate through a seam 212b5′ on the second isolating cover 212b′, so that the two parts of the conductive wire 20161′ and the conductive wire 20162′ are exposed on the second isolating cover 212b′; and as shown in FIG. 12D, a back sheet 205′ is added on the second isolating cover 212b, and the two parts of the conductive wire 20161′ and the conductive wire 20162′ penetrate through a seam 2055′ on the back sheet 205′ for exposing, so that the exposed parts of the conductive wire 20161′ and the conductive wire 20162′ are able to electrically connect with a junction box (not shown in figure), and then an adhesive 2054′ as silicone is coated on the seam 2055′ for seal. As it can be seen, there are three seams 212a5′, 212b5′ and 2055′ in the processes of forming the isolating member between conductive wires. Therefore, the seal may be considered while the solar cell module is assembled. Especially, solar cell module is always exposed under the Sun or stormy and rainy circumstances for quite a long time. Further, the pre-process to vertically bend the conductive wire sets 2016′ may increase the cost to manufacturing as well.
However, only new materials used for lamination process can not permanently solve the problems mentioned above. The most important reason is no more care of wired cables in the solar cell structure. Although solar cells can be well protected, protection of wired cables is not considered. The cables will have power leakage or even cause circuit shortage after long time use. Therefore, a method for overcoming the above problems in manufacturing a solar cell module is still desired.